WSJT-X 2.1.0-rc5 released for testing, incorporating FT4

A new candidate release of WSJT-X has been announced on the WSJT-X home page.

It incorporates a new mode, FT4, a description of which is available here.

Activity has already begun, as seen on the map below from pskreporter. It is too early to say how popular this mode will become, what frequencies it will settle on and whether it will replace or complement FT8.